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Little Folks, Different Strokes(Pediatric Cataracts:
Anesthesia, Anatomy, Surgery )
Alvina Pauline D. Santiago, MDAugust 29, 2015
Disclosure
No proprietary interest with any of the products mentioned.
Objectives of Surgery
• Clear visual axis• Focused retinal image
ME Wilson et al 2012
Problems
• Amblyopia• Reopacification of
ocular media• Anisometropia• Aneisokonia
• Propensity for inflammation
• Different anatomy• Growing eyeball• Changing refraction
ME Wilson et al. 2012
General Anesthesia
Anatomy
Surgery
LITTLE FOLKS, DIFFERENT STROKES
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General Anesthesia: Preop Preparation
• NPO 6 hours
• now clear liquids 2-3 h before surgery
• Better parent acceptance
• Less patient anxiety
Dancy LS, Wallace CT, In Wilson et al 2005 Pediatric Cataract Surgery.
General Anesthesia: Adequate Depth
Laryngeal mask
Endotracheal Tube
Intramuscular /
Intravenous sedation
e.g. ketamine, propofol
• Lower vitreous pressure
• Less Bell’s Phenomenon
Local Peri/Retrobulbar Block
http://www.cybersight.org/bins/volume_page.asp?cid=1-13396-13397-13451
ANATOMY
• Pupil • Cornea with reduced rigidity• Thin sclera with reduced rigidity• Anterior capsule elastic• No hard nucleus• Increased vitreous pressure
Pediatric Pupil
• Newborn to first year of life miotic• Dilates poorly• Too much dilating drops in leaky
blood ocular barrier = corneal haze• Poorly developed dilator muscle• Superviscous and viscous cohesive
OVD adjunct to mydriasis.
SURGERY: INCISION
• Corneal tunnel– Conjunctiva undisturbed– Near the limbus for maximum healing– Sutured with 10-0 synthetic absorbable
• Scleral tunnel– 2-2.5mm from the limbus into clear cornea– Preferred for rigid IOL– Enlarged for IOL– Sutured with 9-0 synthetic absorbable
ME Wilson et al. Cataract Surgery in Children, Trends and Controversies. http://www.aapos.org/client_data/files/2012/479_wilsonhandout.pdf Accessed August 23, 2015.
http://www.reviewofophthalmology.com/
http://www.feather.co.jp
SURGERY: LOCATION OF INCISION
• Superior incision– Wound protected by upper lid and Bell’s– Deep set orbits and overhanging brows not factors– Flat nose bridge makes it easier
• Temporal incision– More space (just like adults)– But easily traumatized in children – Patients w against the rule astigmatism ?– Achieve preoperative astigmatism in 1 month
regardless
ME Wilson et al. Cataract Surgery in Children, Trends and Controversies. http://www.aapos.org/client_data/files/2012/479_wilsonhandout.pdf Accessed August 23, 2015.
Tunnel Incisions
• Do not self seal in children– Children less than 11, not water tight– Especially if combined with anterior vitrectomy– Low corneoscleral rigidity
Basti S, Krishnamachary M, Gupta S. Results of sutureless wound construction in children undergoing cataract extraction. J POS 1996;l33:52-54
http://www.eyeworld.org
SURGERY
• Anterior chamber collapse – Create snug fit for instruments– Bimanual AC former and separate
aspiration if available– appropriate gauge MVR blade – High irrigation setting
ME Wilson et al. Cataract Surgery in Children, Trends and Controversies. http://www.aapos.org/client_data/files/2012/479_wilsonhandout.pdf Accessed August 23, 2015.
SURGERY: ANTERIOR CAPSULORHEXIS
• Highly elastic Anterior Capsule• Staining the AC: ICG, Trypan Blue• High viscosity of OVD• Flatten the anterior capsule• Leading with a cystotome• Capsulorrhexis: CCC
ME Wilson et al. Cataract Surgery in Children, Trends and Controversies. http://www.aapos.org/client_data/files/2012/479_wilsonhandout.pdf Accessed August 23, 2015.
http://i.ytimg.com
Alternatives to Continuous Circular
Capsulorrhexis
• Nischal’s Push-pull technique
• Vitrectorrhexis• Use of radiofrequency
• Cut edge in very young children remains smooth because of capsule elasticity
• In slightly older children, the vitrector creates a slightly scalloped edge
• dissecting microscope and scanning electron microscope have shown that the scallops roll outward to leave a smooth edge.
ME Wilson et al. Cataract Surgery in Children, Trends and Controversies. http://www.aapos.org/client_data/files/2012/479_wilsonhandout.pdf Accessed August 23, 2015.
http://www.medicalmedia.co.il
Vitrectorrhexis
• Venturi pump preferred over peristaltic pump• Separate infusion port• Snug fit of instruments• MVRs• AC maintainer• No need for cystotome• Cut rate 150-300/min• Size smaller than optic
ME Wilson et al. Cataract Surgery in Children, Trends and Controversies. http://www.aapos.org/client_data/files/2012/479_wilsonhandout.pdf Accessed August 23, 2015.
The Anterior Capsulorrhexis
• CCC (preferred > 4 years)– Heavier viscoelastics– Runaway rhexis common – Done well: most resistant to tear
• Vitrectorrhexis (< 4 years)– Easier to perform– Next best in terms of resistance– Runaway less common
• Radiofrequency (any age)– Similar to vitrectorrhexis in advantage
ME Wilson et al 2012
SURGERY: HYDRODISSECT?
• Advantages– Overall reduction in operative time– Less irrigating solution used– Facilitation of lens removal
• Vasavada AR, Trivedi RH, Apple DJ, et al. Randomized, clinical trial of multiquadrant hydrodissection in pedia- tric cataract surgery. AJO. 2003;135:84-88
• Disadvantages– Extension of tears if not CCC– PC rupture in posterior lenticonus and
posterior polar cataractsME Wilson et al. Cataract Surgery in Children, Trends and Controversies.
http://www.aapos.org/client_data/files/2012/479_wilsonhandout.pdf Accessed August 23, 2015.
SURGERY: LENS REMOVAL
• Soft nucleus/cortex but gummy• Aspiration for most• Occasional bursts for ‘gummy” lens material
ME Wilson et al. Cataract Surgery in Children, Trends and Controversies. http://www.aapos.org/client_data/files/2012/479_wilsonhandout.pdf Accessed August 23, 2015.
SURGERY: POSTERIOR CAPSULE & VITREOUS
• Primary posterior capsulotomy & small anterior vitrectomy– Reduce need for 2nd surgery– Visual axis clearer, longer– Nd:Yag difficult in pediatric age group
• Disadvantages– Vitreous violated– More surgery, more inflammation– Does not guarantee prevention of
reopacification
ME Wilson et al. Cataract Surgery in Children, Trends and Controversies. http://www.aapos.org/client_data/files/2012/479_wilsonhandout.pdf Accessed August 23, 2015.
Mousa HG. Slideshare.net
General Rules
<5
• Primary posterior capsulotomy• Vitrectomy
5-8
• Primary posterior capsulotomy• With or without vitrectomy
>8• Intact posterior capsule
ME Wilson et al. Cataract Surgery in Children, Trends and Controversies. http://www.aapos.org/client_data/files/2012/479_wilsonhandout.pdf Accessed August 23, 2015.
SURGERY: VITRECTOMY APPROACH
• Anterior Chamber– Tilts the IOL
• Pars plana/plicata– Preserves IOL position– Pars plana varies– Risk of dialysis and retinal
detachment
Premature infant vs adult globe
From Isenberg SJ, The Eye in Infancy 1994
The Pediatric Pars Plana
Age Nasal Temporal
< 6 mos 2.2 mm 2.5 mm
6-12 mos 2.7 3.0
1-2 yrs 3.0 3.1
2-6 yrs 3.2 3.8
• Temporal ciliary body longer than nasal
Aiello AL, Tran VT, Rao NA, 1992
The Pediatric Pars Plana & Sclerotomy site
Pediatric Pars PlanaAge Nasal Temporal
< 6 mos 2.2 mm 2.5 mm
6-12 mos
2.7 3.0
1-2 yrs 3.0 3.1
2-6 yrs 3.2 3.8
Sclerotomy Site
Aiello AL, Tran VT, Rao NA, 1992
Age Trivedi & Wilson
< 1 yr </= 2mm
1-4 y 2.5
>4 y 3.0
2-6 yrs 3.2
Trivedi and Wilson 2005, in Wilson et al Pediatric Cataract Surgery
Pars Plana Growth
• Most rapid growth
26-35 wks
• 1.87mm• (0.9-2.8mm)
40 wks > 3 mm62
wks
PPV safe only after 62 wks post conception?
Trivedi and Wilson 2005, in Wilson et al Pediatric Cataract Surgery
Nd:YAG in the OR
• Reopacification rate high• Especially if unable to treat
anterior vitreous face• Cost• Availability of YAG laser
mounted on operative microscope
• Need for general anesthesia
Trivedi and Wilson 2005, in Wilson et al Pediatric Cataract Surgery
Photo fr. Wilson ME
RESPECT FOR THE VITREOUS
• Nick the PC with a needle cystotome• Push vitreous with heavy viscoelastic• Proceed with PCCC or vitrectorrhexis• Leave vitreous intact• May or may not aspirate OVD
SURGERY: PRIMARY IOL ISSUES
• Age• To implant or not to implant?• IOL formula to use?• Target refraction• Type of IOL to use• IOL placement?
SURGERY: PRIMARY IOL ISSUE: AGE
• “General consensus IOL for most older children
• IOL implantation during the first year of life still questioned
• 6 mos or younger: CAUTION
Wilson 1996
Trivedi et al 2004
Infant Aphakia Treatment Study Group 2010
Minimize Calculation Errors
• Get a good keratometry reading
• Get a good axial length determination
• Get a good ultrasound• Get a good biometry
• Even if you have to put the patient under general anesthesia
http://www.aitindustries.com
SURGERY: PRIMARY IOL ISSUE: IOL FORMULA
IOL Power
SRKII
SRK-T Holladay
HofferQ
ACCURACY?
Accuracy of IOL Formulas
• 4 formulas studied: SRK II, SRK-T, Holladay, HofferQ• No significant difference in accuracy• Average postop error 1.2-1.4D in all formulas
• high degree of variability – SRK II being the least variable – Hoffer Q being the most variable, – particularly among the youngest group of children with the
axial lengths less than 19 mm
NeelyDE, PlagerDA, BorgerSM, GolubRL. Accuracy of intraocular lens calculations in infants and children undergoing cataract surgery. J AAPOS. 2005;9(2)160–165.
Andreo LK, Wilson ME, Saunders RA. Predictive value of regression and theoretical IOL formula in pediatric intraouclar lens implantation. J Pediatr Ophthalmol Strabismus 1997; 34: 240-243..
Accuracy of IOL Formulas
Prediction Error vs. Desired Refraction
Age at Surgery
Axial Length
NeelyDE, PlagerDA, BorgerSM, GolubRL. Accuracy of intraocular lens calculations in infants and children undergoing cataract surgery. J AAPOS. 2005;9(2)160–165.
SURGERY: PRIMARY IOL ISSUE: TARGET REFRACTION
• Emmetropia in early childhood– Myopic shift– Less anisometropia
• Hyperopia – Mild to Moderate for ages 2-8 years– Amblyogenic– Less problems with myopic shift
ME Wilson et al. Cataract Surgery in Children, Trends and Controversies. http://www.aapos.org/client_data/files/2012/479_wilsonhandout.pdf Accessed August 23, 2015.
IOL Power Selection
AGE (Years) Target Refraction
7 0 to +0.50
6 +1.00
5 +2.00
4 +3.00
3 +4.00
2 +5.00
Weigh:• Refraction of other eye• Risk of amblyopia• Ease of management of
induced anisometropia
SURGERY: PRIMARY IOL ISSUE: IOL PLACEMENT
• In-the-bag (e.g. ALCON SN60 IQ, Rayner Cflex IOL)
• Sulcus placement– PMMA avoids decentration (e.g. ALCON MC
60-BM)– Rayner Cflex IOL– 3 pc foldable acrylic (e.g.) Acrysof MA 60
• Attempt optic capture through AC +/- PC
• Haptic in Sulcus, IOL Optic Capture thru PCCME Wilson et al 2012, Faramarzi et al 2009,
http://www.eye.uci.edu/pix/cataractsurgery.jpg
SURGERY: PRIMARY IOL ISSUE: IOL MATERIAL
ALCON Acrysof PMMA
ME Wilson et al 2012
• Proliferative• Progress more slowly• Less visually significant• 2nd surgery less likely• If Nd:YAG single
sessions
• Fibrous• Progress faster• More visually significant• 2nd surgery likely• Reopacification =
repeated Nd:YAG
Multifocal & Accommodating IOL
• Not recommended when a primary posterior capsulotomy and vitrectomy done
• 2 or more images formed at the retina: immature visual system will choose 1; alternating vision between near image or distant image
• Loss of contrast sensitivity• Eye growth and amblyopia• Myopia with eye growth• Deserves further study at this time
ME Wilson et al. Cataract Surgery in Children, Trends and Controversies. http://www.aapos.org/client_data/files/2012/479_wilsonhandout.pdf Accessed August 23, 2015.
SURGERY: SECONDARY IOL PLACEMENT?
Majority of patients with Primary Posterior Capsulotomy and anterior vitrectomy
• In the bag PCIOL: reopen bag, viscodissection• Sulcus PCIOL: PMMA vs 3-pc acrylic• ACIOL
– 3 pc acrylic transpupillary capture of IOL, haptics in sulcus– Artisan lens
• Retropupillary fixation of Iris Fixated IOL (Mohr)• Transcleral?? As a last resort???
Wilson et al 2012, Wilson et al 2009, Trivedi et al 2005, Wilson et al 2011, Buckley 2007
Transcleral Sutured IOL
• Age dependent myopic shift• 3/33 subluxed IOL
– 10-0 prolene suture spontaneous breakage• 3.5, 8, 9 years
– Survey of 10 pediatric ophthalmologist: • 10 cases at average 5 years
Buckley EG. Hanging by a thread: the long-term efficacy and safety of transcleral sutured IOL in children (an AOS thesis). Trans AOS. 2007;105:294-311
Transcleral Sutured IOL
Buckley EG. Hanging by a thread: the long-term efficacy and safety of transcleral sutured IOL in children (an AOS thesis). Trans AOS. 2007;105:294-311
Conclusion• appears to be a safe and effective
procedure• provided that the suture material
used is stable enough to resist significant degradation over time.
• caution with 10-0 polypropylene suture
• an alternative material or size should be considered.http://vignette3.wikia.nocookie.net
MY PREFERENCE
• Incision corneal, near limbus
• Anterior capsulotomy CCC or vitrectorrhexis
• Lens removal no hydrodissection, no hydrodelineation
• Posterior capsule primary capsulotomy if no IOL
• Vitreous preserve whenever possible
Patient
SurgeryVisual Rehab
When I can’t do biometry: Axial Length from UTZ
• Capozzi P, et al. Corneal curvature and axial length values in children with congenital infantile cataract in the first 42 months of life. Investigative Ophthalmol Vis Sci 2008; 49: 11. 4774-4778.
• Trivedi RH, Wilson M. Keratometry in Pediatric Eyes With Cataract. Arch Ophthalmol. 2008;126(1):38-42. doi:10.1001/archophthalmol.2007.22.
• Gordon RA, Donzis PB. Refractive development of the human eye. Arch Ophthalmol 1985;103:785-789
Date of download: 8/23/2015 The Association for Research in Vision and Ophthalmology Copyright © 2015. All rights reserved.
From: Corneal Curvature and Axial Length Values in Children with Congenital/Infantile Cataract in the First 42 Months of Life
Invest. Ophthalmol. Vis. Sci.. 2008;49(11):4774-4778. doi:10.1167/iovs.07-1564
Figure Legend:
Scatterplot of K m by AL for unilateral and randomly selected single eyes of patients with bilateral cataract.
One hundred years from now, It doesn’t matter what kind of house I lived in,
How much money I had,What positions I held,
Or what my clothes were like.
But the world may be a little better,Because I was important in the life of a child.
-Anonymous
References
1. ME Wilson et al. Cataract Surgery in Children, Trends and Controversies. http://www.aapos.org/client_data/files/2012/479_wilsonhandout.pdf Accessed August 23, 2015.
2. Vasavada AR, Trivedi RH, Apple DJ, et al. Randomized, clinical trial of multiquadrant hydrodissection in pedia- tric cataract surgery. AJO. 2003;135:84-88
3. Basti S, Krishnamachary M, Gupta S. Results of sutureless wound construction in children undergoing cataract extraction. J POS 1996;l33:52-54
4. BuckleyEG.Hangingbyathread:thelong-termefficacy and safety of transcleral sutured IOL in children (an AOS thesis). Trans AOS. 2007;105:294-311
5. Infant Aphakia Treatment Study Group. A randomized clini- cal trial comparing contact lens with intraocular lens correction of monocular aphakia during infancy: grating acuity and adverse events at age 1 year. Arch Oph- thalmol. 2010;128:810-8.
6. Faramarzi A, Javadi MA. Comparison of 2 techniques of intraocular lens implantation in pediatric cataract sur- gery. J Cataract Refract Surg. 2009;35:1040-5. WilsonMEJr,EnglertJA,GreenwaldMJ.In-the-bagsec- ondary intraocular lens implantation in children. J AAPOS. 1999;3:350-5
7. TrivediRH,WilsonME,FaccianiJ.Secondaryintraocular lens implantation for pediatric aphakia. J AAPOS 2005;9:346-52 8. WilsonME,HafezGA,TrivediRH.Secondaryin-the-bag IOL implantation in children who have been aphakic since early infancy. J
AAPOS 2011;15:162-6 9. Andreo LK, Wilson ME, Saunders RA. Predictive value of regression and theoretical IOL formula in pediatric intraouclar lens
implantation. J Pediatr Ophthalmol Strabismus 1997; 34: 240-243..10. NeelyDE, PlagerDA, BorgerSM, GolubRL. Accuracy of intraocular lens calculations in infants and children undergoing cataract
surgery. J AAPOS. 2005;9(2)160–165.11. Moore DB, Zion IB, Neely et al. Accuracy of biometry in pediatric cataract extraction with primary intraocular lens implantation.
J Cat Refract Surg 2008; 34 (11): 1940-1947.12. Wilson ME, Trivedi RH, Pandey SK. Pediatric Cataract Surgery, Techniques, Complications and Management. PA, Lippincott
Williams & Wilkins, 2005.13. Aiello AL, Tran VT, Rao NA. Postnatal development of the ciliary body and pars plana. A morphometric study in childhood. Arch
Ophthalmol 1992; 110: 802-805.